[arvinsim]

I got tired of using CSS frameworks where classes are used to define widths. Now, I much prefer frameworks that support semantic style like Susy.

http://susy.oddbird.net/

[smt88]

If you use SCSS or LESS, you can inherit the widths into semantic classes. So Bootstrap can be as semantic as you want it to be.

[ffn]

Just be sure to use @include and not @extend, otherwise you'll wind up blowing through your allowed selector ration and wind up wonky css bugs that you will never be able to resolve without re-writing everything.